The present invention relates to a method for supplying visually encoded image data, preferably in the form of at least one bar code, for displaying through a mobile device, a security element of such an end device, an image data generation unit, an image data management unit, as well as a system comprising a device information unit, an image data generation unit and at least one mobile device.
Bar codes, in the form of 1D and 2D bar codes, have been traditionally affixed on printed matter and on physical objects to be read by appropriate bar code scanners. There are many types of bar codes, such as PDF417, microPDF417, MaxiCode, DataMatrix (standard, inverse), QR Code (standard, inverse and micro), Han Xin, Aztec (standard, inverse), etc. and variants. These codes generally work with the same imaging principle.
With increasing availability of mobile devices with auto-focus cameras and bar code scanners, bar codes, in particular 2D bar codes, have started to gain a big role in mobile marketing. The subscribers use their mobile phone to read a bar code that will bring them to a website, display information, and send SMS, etc. The next stage of mobile bar code has started gaining traction, and that is to issue boarding passes, tickets, store cards, coupons, etc. to the mobile phones and to display these bar codes to be read by a cashier, movie counter, shops, etc. Although the same types of bar codes are used, new sets of unanticipated problems have emerged that have never been addressed in use prior cases with printed bar codes.
One of these problems is, for example, that bar codes, which were generated on the basis of identical starting data, sometimes may appear very different on different end devices. On an end device which comprises a comparatively large display with very high resolution a bar code may appear too small for being captured by a reading device, since the reading device does not support such a resolution. The same bar code may possibly be displayed only partially on an end device with small display and very low resolution, and therefore not be captured correctly by the reading device, either.
Problems also arise by a user changing his end device, for example replacing an old end device by a new end device. The representation parameters for the optimal generation and representation of a bar code were known for the old end device, but these parameters will normally no longer be usable for the new end device, as this has deviating device properties.